Bart,
Humor, no matter how weak, is still humor.
Many programs leave behind traces that don't get deleted when you drag an
application to the trash and empty it. Although it won't find all the files,
Spotlight could help you find and eliminate traces left behind.
Removing the plists, downloaded files and directories eliminates another
potential source of conflicting code.
If you supplied more detail on what you did to attempt to resolve the
problem, I (and others) could offer less generic advice. Please supply as much
detail as you can about the issue and its symptoms - when and how it
started, what software you installed and changes you made to your system
before and after you noticed the problem, etc., and the remedial steps you
have taken.
It's possible that the P2P software itself is not the source of the problem. Are
any other applications showing the same symptoms?
-Wayne